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Trait scala.Product

trait Product extends Equals

Base trait for all products, which in the standard library include at least scala.Product1 through scala.Product22 and therefore also their subclasses scala.Tuple1 through scala.Tuple22. In addition, all case classes implement Product with synthetically generated methods.

Source
Product.scala
Since

2.3

Linear Supertypes
Equals, Any
Known Subclasses
None, Option, Product1, Product10, Product11, Product12, Product13, Product14, Product15, Product16, Product17, Product18, Product19, Product2, Product20, Product21, Product22, Product3, Product4, Product5, Product6, Product7, Product8, Product9, ScalaReflectionException, Some, StringContext, Tuple1, Tuple10, Tuple11, Tuple12, Tuple13, Tuple14, Tuple15, Tuple16, Tuple17, Tuple18, Tuple19, Tuple2, Tuple20, Tuple21, Tuple22, Tuple3, Tuple4, Tuple5, Tuple6, Tuple7, Tuple8, Tuple9, UninitializedFieldError, Found, InsertionPoint, StringView, Empty, ::, Nil, Insertion, Modification, Deadline, AsJavaBiConsumer, AsJavaBiFunction, AsJavaBiPredicate, AsJavaBinaryOperator, AsJavaBooleanSupplier, AsJavaConsumer, AsJavaDoubleBinaryOperator, AsJavaDoubleConsumer, AsJavaDoubleFunction, AsJavaDoublePredicate, AsJavaDoubleSupplier, AsJavaDoubleToIntFunction, AsJavaDoubleToLongFunction, AsJavaDoubleUnaryOperator, AsJavaFunction, AsJavaIntBinaryOperator, AsJavaIntConsumer, AsJavaIntFunction, AsJavaIntPredicate, AsJavaIntSupplier, AsJavaIntToDoubleFunction, AsJavaIntToLongFunction, AsJavaIntUnaryOperator, AsJavaLongBinaryOperator, AsJavaLongConsumer, AsJavaLongFunction, AsJavaLongPredicate, AsJavaLongSupplier, AsJavaLongToDoubleFunction, AsJavaLongToIntFunction, AsJavaLongUnaryOperator, AsJavaObjDoubleConsumer, AsJavaObjIntConsumer, AsJavaObjLongConsumer, AsJavaPredicate, AsJavaSupplier, AsJavaToDoubleBiFunction, AsJavaToDoubleFunction, AsJavaToIntBiFunction, AsJavaToIntFunction, AsJavaToLongBiFunction, AsJavaToLongFunction, AsJavaUnaryOperator, FromJavaBiConsumer, FromJavaBiFunction, FromJavaBiPredicate, FromJavaBinaryOperator, FromJavaBooleanSupplier, FromJavaConsumer, FromJavaDoubleBinaryOperator, FromJavaDoubleConsumer, FromJavaDoubleFunction, FromJavaDoublePredicate, FromJavaDoubleSupplier, FromJavaDoubleToIntFunction, FromJavaDoubleToLongFunction, FromJavaDoubleUnaryOperator, FromJavaFunction, FromJavaIntBinaryOperator, FromJavaIntConsumer, FromJavaIntFunction, FromJavaIntPredicate, FromJavaIntSupplier, FromJavaIntToDoubleFunction, FromJavaIntToLongFunction, FromJavaIntUnaryOperator, FromJavaLongBinaryOperator, FromJavaLongConsumer, FromJavaLongFunction, FromJavaLongPredicate, FromJavaLongSupplier, FromJavaLongToDoubleFunction, FromJavaLongToIntFunction, FromJavaLongUnaryOperator, FromJavaObjDoubleConsumer, FromJavaObjIntConsumer, FromJavaObjLongConsumer, FromJavaPredicate, FromJavaSupplier, FromJavaToDoubleBiFunction, FromJavaToDoubleFunction, FromJavaToIntBiFunction, FromJavaToIntFunction, FromJavaToLongBiFunction, FromJavaToLongFunction, FromJavaUnaryOperator, Either, LeftProjection, Failure, Left, Right, Success, Try, Call, Cont, Done, RightProjection

Abstract Value Members

abstract def canEqual(that: Any): Boolean

A method that should be called from every well-designed equals method that is open to be overridden in a subclass. See Programming in Scala, Chapter 28 for discussion and design.

that

the value being probed for possible equality

returns

true if this instance can possibly equal that, otherwise false

Definition Classes
Equals

abstract def getClass(): Class[_ <: AnyRef]

Returns the runtime class representation of the object.

returns

a class object corresponding to the runtime type of the receiver.

Definition Classes
Any

abstract def productArity: Int

The size of this product.

returns

for a product A(x1, ..., xk), returns k

abstract def productElement(n: Int): Any

The nth element of this product, 0-based. In other words, for a product A(x1, ..., xk), returns x(n+1) where 0 <= n < k.

n

the index of the element to return

returns

the element n elements after the first element

Exceptions thrown

IndexOutOfBoundsException if the n is out of range(n < 0 || n >= productArity).

Concrete Value Members

final def !=(arg0: Any): Boolean

Test two objects for inequality.

returns

true if !(this == that), false otherwise.

Definition Classes
Any

final def ##(): Int

Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException.

returns

a hash value consistent with ==

Definition Classes
Any

def +(other: String): String

Implicit
This member is added by an implicit conversion from Product toany2stringadd[Product] performed by method any2stringadd in scala.Predef.
Definition Classes
any2stringadd

def ->[B](y: B): (Product, B)

Implicit
This member is added by an implicit conversion from Product toArrowAssoc[Product] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc
Annotations
@inline()

final def ==(arg0: Any): Boolean

Test two objects for equality. The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

returns

true if the receiver object is equivalent to the argument; false otherwise.

Definition Classes
Any

final def asInstanceOf[T0]: T0

Cast the receiver object to be of type T0.

Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

returns

the receiver object.

Definition Classes
Any
Exceptions thrown

ClassCastException if the receiver object is not an instance of the erasure of type T0.

def ensuring(cond: (Product) => Boolean, msg: => Any): Product

Implicit
This member is added by an implicit conversion from Product toEnsuring[Product] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: (Product) => Boolean): Product

Implicit
This member is added by an implicit conversion from Product toEnsuring[Product] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: Boolean, msg: => Any): Product

Implicit
This member is added by an implicit conversion from Product toEnsuring[Product] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: Boolean): Product

Implicit
This member is added by an implicit conversion from Product toEnsuring[Product] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def equals(arg0: Any): Boolean

Compares the receiver object (this) with the argument object (that) for equivalence.

Any implementation of this method should be an equivalence relation:

    It is reflexive: for any instance x of type Any, x.equals(x) should return true.It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and only if y.equals(x) returns true.It is transitive: for any instances x, y, and z of type Any if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.

If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is usually necessary to override hashCode to ensure that objects which are "equal" (o1.equals(o2) returns true) hash to the same scala.Int. (o1.hashCode.equals(o2.hashCode)).

returns

true if the receiver object is equivalent to the argument; false otherwise.

Definition Classes
Any

def formatted(fmtstr: String): String

Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).

Implicit
This member is added by an implicit conversion from Product toStringFormat[Product] performed by method StringFormat in scala.Predef.
Definition Classes
StringFormat
Annotations
@inline()

def hashCode(): Int

Calculate a hash code value for the object.

The default hashing algorithm is platform dependent.

Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0. However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure to verify that the behavior is consistent with the equals method.

returns

the hash code value for this object.

Definition Classes
Any

final def isInstanceOf[T0]: Boolean

Test whether the dynamic type of the receiver object is T0.

Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

returns

true if the receiver object is an instance of erasure of type T0; false otherwise.

Definition Classes
Any

def productElementName(n: Int): String

The name of the nth element of this product, 0-based. In the default implementation, an empty string.

n

the index of the element name to return

returns

the name of the specified element

Exceptions thrown

IndexOutOfBoundsException if the n is out of range(n < 0 || n >= productArity).

def productElementNames: Iterator[String]

def productIterator: Iterator[Any]

An iterator over all the elements of this product.

returns

in the default implementation, an Iterator[Any]

def productPrefix: String

A string used in the toString methods of derived classes. Implementations may override this method to prepend a string prefix to the result of toString methods.

returns

in the default implementation, the empty string

def toString(): String

Returns a string representation of the object.

The default representation is platform dependent.

returns

a string representation of the object.

Definition Classes
Any

© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.13.0/scala/Product.html